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Accurate determination of lattice parameters based on Niggli reduced cell theory by using digitized electron
Yi Yang1, Canying Cai1, Jianguo Lin1
1School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China.
Micron (Oxford, England : 1993)
|February 17, 2017
Summary
This study introduces an improved method for measuring crystal lattice constants using Niggli reduced cell theory and electron diffraction. The technique significantly enhances measurement accuracy for micro/nano crystals.
Area of Science:
- Materials Science
- Crystallography
- Electron Microscopy
Background:
- Accurate determination of lattice constants is crucial for understanding material properties.
- Traditional methods using double tilt holders can be complex and less precise for micro/nano crystals.
Purpose of the Study:
- To develop and validate a more accurate method for measuring lattice constants of micro/nano crystals.
- To apply Niggli reduced cell theory with electron diffraction for enhanced precision.
Main Methods:
- Utilized Niggli reduced cell theory combined with electron diffraction patterns.
- Employed a digitized algorithm and least square optimization on three digitized micrographs.
- Direct measurement of lattice vector lengths and angles from electron micrographs, bypassing the need for a double tilt holder.
Main Results:
- The Niggli reduced cell method demonstrated a significant enhancement in lattice constant measurement accuracy.
- Achieved a maximum error of 1.6% for lattice constant lengths and 0.3% for angles.
- Successfully determined reciprocal and real Bravais lattices for tested materials.
Conclusions:
- The Niggli reduced cell method offers a more accurate and direct approach to lattice constant determination.
- This method is effective for micro/nano crystals, improving upon conventional techniques.
- Validated through successful application to Mg4Zn7, a precipitate phase in nickel-base superalloys, and Ba4Ti13O30.
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